Expanding spray foam question

[Bapa323]

Can anyone tell me if there is an expandable spray foam product that is safe for direct contact with the outside of class A chimney pipe?
I want to seal air gaps between my roof flashing and chimney pipe to keep insects out. I have a storm collar for rain but it isn't insect proof.

 

[stoveliker]

My class A is requiring a 2" gap before any combustible, per its UL listing.
Do you have a clearance distance?

 

[Mikerodrig27]

I don't know a spray foam that is non-combustible. Mineral wool is non-combustible. However, I don't have any experience using it around chimney pipe

 

[Bapa323]

All Class A requires a minimum of 2" clearance to combustibles I thought?
Anyway, yes mine does. That's why I'm asking if anyone is aware of a non-combustable expanding spray foam.

 

[stoveliker]

I would get sheet metal (flashing) precisely cut to size, and silicone caulk for the seams to do that.

 

[bholler]

Can anyone tell me if there is an expandable spray foam product that is safe for direct contact with the outside of class A chimney pipe?
I want to seal air gaps between my roof flashing and chimney pipe to keep insects out. I have a storm collar for rain but it isn't insect proof.

No spray foam. Is very combustible

 

[begreen]

Use metal screening if insects are a bad problem.

 

[clux]

I saw a spray in foam insulation fire in a steel quonset style potato cellar once.

I'd never put it anywhere in my house after that.

 

[Bapa323]

Use metal screening if insects are a bad problem.

I have a lot of yellow jackets and European Hornets in the area and want to keep them out of my attic. Metal screen might just work if I can figure out how to attach it.

 

[stoveliker]

If you can find metal (!) window screens. Normal screen may be too coarse.

 

[Ashful]

We only have one European hornet. We call him @stoveliker.

 

[Bapa323]

I think I have found my solution. What do you think?

 

[stoveliker]

I wouldn't. For hot air ducts.
While your chimney should not get to 600 F, I would still be hesitant.

Moreover, this tape is not non-combustible, and hence illegal to be within the clearance distance of your chimney.

 

[stoveliker]

We only have one European hornet. We call him @stoveliker.

Methinks whatever cocktail you are drinking is getting to your head.

Stick to a cognac before dinner ;-)

 

[Bapa323]

I wouldn't. For hot air ducts.
While your chimney should not get to 600 F, I would still be hesitant.

Moreover, this tape is not non-combustible, and hence illegal to be within the clearance distance of your chimney.

Good point

 

[Ashful]

Methinks whatever cocktail you are drinking is getting to your head.

Stick to a cognac before dinner ;-)

Nah, that was sober. Too busy tonight.

 

[Mikerodrig27]

 

[brenndatomu]

I saw a spray in foam insulation fire in a steel quonset style potato cellar once.

I'd never put it anywhere in my house after that.

I have some spray foam in the house...if I had it to do over again I'd have Airkrete put in instead...way better product, and won't burn.

Home | Airkrete - All Green Light Weight Cement Insulation!

The most environmentally safe, the only fireproof insulation on the planet, gives off zero noxious gases and odors, and is 100% pest and mold resistant!

www.airkrete.com

I know they make "firestop" spray foam, but when I read up on it there really seems to be very little difference from regular ole spray foam...other than the color...so not sure what the point is really?! (I know why you use it, just not why not to just use standard spray foam)
Edit: After watching the above video it appears that maybe it is just less flammable than the regular foam...

 

[brenndatomu]

Use metal screening if insects are a bad problem.

Stainless steel screen...
Amazon product ASIN B0B3XPLNZG

 

[GrumpyDad]

Can anyone tell me if there is an expandable spray foam product that is safe for direct contact with the outside of class A chimney pipe?
I want to seal air gaps between my roof flashing and chimney pipe to keep insects out. I have a storm collar for rain but it isn't insect proof.

what is your plan w/ the giant hole at the top of the chimney?

 

[stoveliker]

what is your plan w/ the giant hole at the top of the chimney?

The stove door?

 

[begreen]

Can anyone tell me if there is an expandable spray foam product that is safe for direct contact with the outside of class A chimney pipe?
I want to seal air gaps between my roof flashing and chimney pipe to keep insects out. I have a storm collar for rain but it isn't insect proof.

None, use metal, stainless screening.

 

[Ashful]

Hello. Just have a quick question. Did you have an idea of what it would cost to spray foam insulate a basement that is being refinished? It is stripped down to the studs and ready for insulation now. Will get a few quotes next week but thought I would ask you experts here. House is roughly 1700 square feet

In 2015, I paid the following:

R21+ on roof bays (570 sq.ft.): $2340
R21+ on walls (800 sq.ft.): $3040

They charged me an extra $150 to cover exposed joists and another $150 to cover exposed rafters, it's an old timber frame structure that was being finished with these partly exposed. They also had to bring in a generator to power the equipment, since it pulled more than the 60 amps I had available at that location, which cost an extra $300.

They ended up spraying at least 1.5x their min spec, or more, so final job probably averaged closer to R35. I was very happy with the result, but I'd want to do some research before using this product in a basement, where mold could be an issue. My job was in a carriage barn, all above grade.

 

[stoveliker]

Is that 800 sq ft wall space, or the (8 ft tall?) walls around an 800 sq ft space? The latter would, for a square space, be 1600 sq ft wall space.

 

[Ashful]

Is that 800 sq ft wall space, or the (8 ft tall?) walls around an 800 sq ft space? The latter would, for a square space, be 1600 sq ft wall space.

800 sq.ft. wall space, as in 12 ft. high x 80 ft perimeter, minus 160 sq.ft. in doors.

Rough number, I didn't bother adding gable ends or subtracting windows, which probably roughly cancel each other.